K-Ar Dating of Sediments

Abstract

It is particularly appropriate to review the subject of K-Ar dating of sediments in a volume that honours Professor Gentner. Much of the earliest work on the testing of the build-up and possible escape of Ar⁴⁰ in K-bearing minerals of known age was carried out in his laboratory. Evaporite minerals from sedimentary sequences were chosen because of high content of potassium and well-established geologic age. The studies involved the branching ratio in the K⁴⁰ decay scheme, the mechanism of argon loss and diffusivity constants, as well as the suitability of minerals for dating. These subjects subsequently became areas of extensive research by other laboratories.